Weight loss in elderly orthopaedic patients leads to bone loss

Abstract

BackgroundThe number of patients with osteoporosis or low bone mass is increasing annually. Weight loss is reportedly associated with bone loss and is a strong predictor of osteoporosis. It was still not clear the relationship between weight loss and bone loss in the elder.MethodsThe study included 520 patients aged ≥65 years (178 men and 342 women). Age, gender, weight, and height were recorded. Femoral neck bone mineral density and T-score were investigated using a dual-energy X-ray absorptiometry scanner. Blood calcium (Ca), phosphorus (P), albumin (ALB), alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglyceride (TG), total cholesterol (TC), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) levels were measured. Patients were classified by gender (male and female), age (65-79 years and ≥80 years), and T-score: normal, osteopenia and osteoporosis.ResultsAge, gender, body mass index (BMI), ALP and TG were independent factors for osteoporosis. For the 65-79 and ≥80 year age groups, female patients presented lower T-scores than males. Ca, P, ALB, ALP, TC, HDL and LDL levels were significantly different between men and women in the 65-79 year age group. In addition, BMI and TG levels were significantly decreased in osteoporotic patients compared with normal bone mass patients. TC levels declined in 65-79 year-old male and female patients with osteoporosis. In the group of women aged ≥80 years, osteoporotic patients showed significantly increased ALP levels. Furthermore, we found positive correlations between BMI and TG levels in the groups of male and female patients. However, we found no significant differences in ALB, Ca, P, HDL and LDL levels in osteoporotic compared to normal bone mass patients.Conclusion Osteoporotic patients showed significantly decreased BMI and TG levels compared with those with normal bone mass. BMI was showed positive correlations with TG levels in male and female patients. These results indicate a correlation between weight loss and bone loss and a correlation between lipid profiles and bone mass.